When creating a Derived Table in Ad Hoc, and entering a valid query such as:
select table1.field1 as f1
, concat(' Field2:',table1.field2,' Field3:',table1.field3) as f2_and_f3
, table1.field4 as f4
, FROM_UNIXTIME(table1.field_unix_timestamp) as d1
The field f1_and_f2, will not appear in the list of fields to add to the derived table.
It will be only:
Other SQL functions, such as FROM_UNIXTIME(), LENGTH(), IF(), CASE, etc, work fine.